Quasi-static load bearing behaviour of hybrid grouted joints

Abstract

In offshore applications, high-strength grout is used to connect tubular steel sections. Grouted connections rely on welded shear keys to ensure sufficient interlocking of the grout-steel interface. These shear keys lead to stress concentrations, which in turn lead to fatigue cracks, and local damage of the grout. The hybrid grouted joint is a newly developed connection that is characterised by a multi-layered composition. In contrast to state-of-the-art grouted joints, hybrid grouted joints include thin adhesive layers, which are applied on the steel surfaces prior to grouting. The new connection type is in the focus of a recently finished research project. This paper presents selected results concerning the quasi-static load-bearing capacity under axial loading. The experimental campaign aimed at identifying and quantifying various aspects that influence the connection's performance. Different adherent combinations, varying overlap lengths, load directions and systematically induced imperfections were evaluated.